Chlorpyrifos dislodgeable turf residues

Somewhat water-soluble pesticides such as acid herbicides will be washed from foliar surfaces and into subsurface soils by rainfall. For example, dislodge-able turf residues of 2,4-D after a 2.54-cm rainfall have been reported to be only 1-5% of those found at 4-8 h after application (Nishioka et al., 1996 USEPA, 1997c). However, dew or rain on aged turf residues may increase their dislodgeability (Nishioka et al, 1996). OP insecticides are semivolatile and will vaporize from surfaces after applications. Chlorpyrifos vaporizes rapidly from lawns if applied in aqueous formulations. Diazinon, which is used on lawns as well as indoors, dissipates even more rapidly. However, the persistence of OP... 

Goh, K.S., S. Edmiston, K.T. Maddy, D.D. Meinders and S. Margetich (1986). Dissipation of dislodgeable foliar residue of chlorpyrifos and dichlorvos on turf. Bull. Environ. Contam. Toxicol, 37, 27-32. 

Table 2 Liquid Turf Study Adult Dermal Dose of Chlorpyrifos Based on Dislodgeable Residue Data...

Black, K.G. and R.A. Fenske (1996). Dislodgeability of chlorpyrifos and fluorescent tracer residues on turf Comparison of wipe and foliar wash sampling techniques. Arch. Environ. Contam. Toxicol, 31, 563-570. 

Sears, M.K., C. Bowhey, H. Braun, G.R. Stephenson (1987). Dislodgeable residues and persistence of diazinon, chlorpyrifos and isofenphos following their application to turf-grass, Pesticide Sci, 20, 223-231. 

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